1. Field of the Invention
The present invention relates to a backlight apparatus, and more particularly, to a guiding element in the backlight apparatus.
2. Description of the Prior Art
A liquid crystal panel does not emit light itself, and therefore a backlight apparatus is needed for the liquid crystal panel to display images normally.
Please refer to FIG. 1. Conventionally a backlight apparatus of a liquid crystal panel includes a light source 1, a reflector 2, a light guide plate 3 and a reflective plate 4. The light source 1 provides light for the backlight apparatus, and the reflector 2 surrounds the light source 1 for reflecting light provided from the light source 1 into the light guide plate 3. The light guide plate has a front surface 3C and a rear surface 3B. An end 3A of the light guide plate is adjacent to the light source 1 for receiving light from the light source 1. There is a plurality of reflective patterns 3D disposed on the rear surface 3B, and the reflective pattern 3D is a convexity or a concavity. The reflective plate 4 is disposed below the light guide plate 3 for reflecting light passing through the rear surface 3B of the light guide plate 3 back to the light guide plate 3. After the light from the light source 1 enters the light guide plate 3 through the end 3A, the light is repeatedly total internally reflected between the front surface 3C and the rear surface 3B of the light guide plate 3 while proceeding away from the light source 1. The reflective pattern 3D changes the reflective angles of the light for refracting the light out of the light guide plate 3 in order to provide light for the liquid crystal panel.
Please refer to FIG. 2. The conventional reflective pattern 3D is a single convexity or a single concavity. Take the convex reflective pattern 3D for example; the reflective pattern 3D is a single convexity when viewed from any direction, and only the effective reflective area 3D1 and 3D2 (the areas facing the light source) can reflect or refract the light to the front surface 3C. Thus, light is not reflected or refracted out of the light guide plate effectively and cannot proceed away from the light source, causing the uniformity of light in the whole light guide plate to be not good.
Consequently, it is to be solved that how to increase the reflecting effect of the light guide plate and raise the uniformity of light in the light guide plate.